The present invention generally relates to electronic devices, and particularly relates to the use of cryptographic processing to verify that an electronic device has been disabled.
As marketplaces and regulatory regimes become more sensitive to the environmental impacts of the disposal of consumer products, mobile phone manufacturers and other makers of electronic devices are increasingly likely to have an economic stake in how their products are processed upon disposal. Regulations and/or market forces may require, for instance, that these manufacturers recycle components from devices that are no longer wanted.
In many situations, disposal, recycling, and other end-of-life handling of products is likely to be contracted to companies unrelated to the manufacturers. In a typical business model, these contracted companies may charge the device manufacturer on a per-device basis for processing discarded products. Especially in the mobile phone industry, where various “grey” markets have flourished from time to time, such a business model may encourage fraud, where a manufacturer is charged for handling of devices that were not actually processed or that were diverted to uses not authorized by the producer.
To counter such fraud, a manufacturer might require that the contracted company disposing the products provide a list of device-specific serial numbers, such as the International Mobile Equipment Identifiers (IMEI) used with mobile phones, corresponding to the disposed products. The phone producer may then validate the submitted identifiers against a list of produced units before authorizing payment to the contractor. However, this process does not prove that the devices were actually taken out of service.